A liquid crystal display device has advantages of low power consumption, no radiation, etc., and plays a leading role in a field of flat panel display.
A liquid crystal panel in the related liquid crystal display device usually comprises an array substrate and a color filter substrate arranged opposite to each other, and a liquid crystal layer filled between the array substrate and the color filter substrate, wherein the array substrate is provided with a plurality of thin film transistors and a plurality of pixel electrodes, the pixel electrodes are connected to drain electrodes of the thin film transistors, and the color filter substrate is provided with the common electrode corresponding to the pixel electrodes. When the pixel electrode is charged via the thin film transistor, an electric field is formed between the pixel electrode and the common electrode, so as to control liquid crystal molecules in a corresponding liquid crystal region of the pixel electrode to deflect and further realizing a liquid crystal display function. Generally, in order to align the liquid crystal molecules in certain direction, such liquid crystal panel has an alignment film set to form a certain pretilt angle. A known method for manufacturing the alignment film is a rubbing processing method, including rubbing a thin film formed on a substrate and made of a macromolecular compound such as polyimide in a direction with a cloth such as artificial silk, etc.